I'm thinking of traveling out to West Yellowstone this September and leaving around the end of October.

I'm curious when you should worry about being caught in a snowstorm. Do they get any in October?

Scares me to death the thought of driving down a mountain on snowy/icy roads towing a 5th wheeler.

Jim

Hi,

For the Week of Oct 6, 2011 the low temperature was about 28 F. That means snow is quite possible. The high for the week was 69 F.

http://classic.wunderground.com/history/ai...klyHistory.html

You can never say for sure what the weather will be like anywhere. We wanted to go to Glacier NP and back through Yellowstone in the fall of 2010, but we could not get away until the middle of Sept. “People” told us that would be too late to go because it would be cold and possibly snowing, so we opted for Gunnison, Moab and Durango. We kept an eye on the Glacier weather, and it was great the whole time we would have been there. We almost headed out for there anyway.

Then last year we decided to try Glacier/Yellowstone again. We were in Glacier around the middle of Sept. and again the weather was wonderful, even a little unseasonably warm. We had cool, but not real cold nights (maybe 1-2 light freezes). We got to Yellowstone around the end of Sept and were there through the first part of Oct., and again the weather was fantastic and on the warm side. It was so warm, in fact, that the elk had not yet come down from the high country, so we missed seeing them, and other animals were not moving around very much either because of the heat.

But that was the last two years. This year they may get snow very early. Even so, in talking to the locals, they told us that if they do get an early snow, it is not very big, and usually the weather warms up again quickly, so it does not stay on the roadways. We figured if it did snow we could “hunker down” and enjoy it for a few days. I also think if you watch the weather closely, you will have enough warning to leave before bad weather gets there. If you do go, have a great trip. It is a beautiful area.

As others have already indicated, snow and cold (nights <32F) are quite possible before the end of September. By the end of October, that type of weather is likely. What may be as important as the weather is what facilities are available in October. Many RV parks shut down around October 1st and many other tourist businesses (shops, restaurants, etc.) in bordering communities (West Yellowstone, Gardiner, etc.) also end their season in October. 10+ years ago, West Yellowstone was the first place I ever saw a frozen water hose on 9/30 the last day the RV park was open. Water availability becomes an issue at the parks that are sitill open in October. Then there is the question of access to YNP itself and the sights if there is a heavy snow.

I think Yellowstone is the only place in the 48 that can receive snow on the 4th of July. We have been in snow storms here in mid May but got out before the snow was to deep. You should be OK in Sep.

Last year, in mid October, we drove through a blizzard on I80 across Wyoming. We had some cold rain/ice pellets the week prior in West Yellowstone. We travel most years out West in the Wintertime and although we watch the weather, we do occasionally get caught in the snow.
We have spent January in the Grand Canyon RV Park and shared it with the deer and only a few other campers. From there, we drove over to Bryce and Zion National Parks. The facts are that from September on, you can get caught in Snow at any time in the Western mountains. I always carry tire chains with me, even though we try to avoid driving on heavily snow covered roads. The chains are used primarily to get in to RV parks and out of them during the Winter. A lot of parks do not have provisions to remove a lot of snow quickly and unless we want to be stranded for a week or more, I just put on the chains and head out towards our next destination.
Anyone that has traveled during the Winter months knows that the world does not shut down when it snows. People still go to work and trucks still make deliveries. What we do is watch the weather and try to avoid the worst storms. When we do get caught in some snow, I just drive carefully, leave a large gap between me and the vehicle in front, and enjoy our travels.
Those that don't like snow in the Winter travel to our home state of Florida. We leave and head out to where we know we will probably run into snow.
We are in a Class A and towing a vehicle behind us.

September and early October should be fine. After that, I am not sure you can find anything open. In a normal year, you will expect to find snow by Halloween in West Yellowstone and the park for sure.

I think I heard this morning on the Weather Channel that it was 8F in West Yellowstone. It made me wonder whether or not the OP is currently in the Yellowstone area or did he take the majority advice in this thread and not stay too far into October. A little later there was a story about a terrible multi-vehicle accident on I80 near Cheyenne, WY. The main culprit was what is known as "black ice". While Cheyenne is hundreds of miles south east of Yellowstone, this incident is a good cautionary example of how dangerous winter weather can be.